Colt 720 dx and colt 510 audio deviation ajustment help

[original45]

Audio seems quiet on both these radios the 720 more so, I would like to use a little switch cleaner and increase the audio a touch .
Does anyone know the vr numbers and position of them on the boards so I don't ajust by mistake something else.

It would be handy if someone's has the vr listed for rf gain,signal meter ,squelch ,tx needle so on for future reference.
Thank you

[163TM847]

FM deviation will be on the FM boards, On the Colt 510 FM board there is sometimes two VRs, One for RX audio and one for TX audio.

So im guessing the 720 had FM afterall ? If so there is only one VR on the FM board so you cant really miss it.

[original45]

Nick it's a mystery. It has a sticker over the off on anl saying Am ,it had one over anl too you can see the sticker outline I assume fm however it only seems to work on am and does nothing but eliminate noise .

It has me confused I must say.
I still am none the wiser as to if it has fm board or not as I'm unsure what it would look like and where.

Just took casing off, is the fm board a smaller board raised off main board situated just behind channel selector switch unit.
Has code of00s008a0x . The anl switch has just two wires to it black and brown. All other switches seem to do what they should also.

Just to add update ,it has no fm board, just found a image picturing fm board which should be on opposite side to the other smaller board.
Disappointing that. Can't understand why the am sticker then unless front pannel swap.

So in this case is their a pot to turn up audio as such for am on the main board

[Mitch]

...
I still am none the wiser as to if it has fm board or not as I'm unsure what it would look like and where.
...

Here's the FM board in a Formac 88 (PTZZ033AOX), it should look the same as yours.

[original45]

Cool Mitch yes I spotted that in the 510. rv 501 anti clock I think to increase., thank you. Any idea if I can turn up and if so how audio on a am only no fm board colt 720

[Mitch]

Yes, anti-clockwise to increase deviation (mine's up nearly full). AM mod adjust is RV2 on Cybernet 092/094/106 boards but it doesn't boost audio at all, it only adjusts the mod limiter (ALC), it can reduce it by making it sound clippy but that's all. If you need more AM mod you need a power mic or less RF output. AM works in a different way to FM so not as easy to adjust.

[original45]

Cheers Mitch, the standard original mic condenser is kaput and I did test the radio eith another cybernet standard mic which was reported quiet but apparently sounded great with the leson base mic.

I did pick up a 510 powrr mic but seems to also fail to work despite New mic piece.

Thanks Mitch for explaining I shall leave it as is and sort a power mic.makes sense .

Thanks again